3. at a convention. jim and his three friends
each bought three raffle tickets. at the time of
the drawing, 400 tickets had been sold. what
is the probability that either jim or one of his
friends will win?

Icould really use some with this question.

He mass of a single atom of carbon can be found by dividing the atomic mass (12.01 g) by 6.022 x 10^23. which is the mass of a single carbon atom, correctly written in scientific notation with the correct number of significant figures?

Damon makes 20 cups of lemonade by mixing lemon juice and water. the ratio of lemon juice to water is shown in the tape diagram. lemon juice\text{lemon juice} lemon juice water\text{water} water how much lemon juice did damon use in the lemonade? cups